Method of packaging coils

ABSTRACT

The method of packaging coils uses a tear-resistant packaging tube having openings at either end. The tear-resistant packaging tube is made from at least one layer of material. The coil is generally cylindrical and defines a length, a circumference, an inside diameter, and an opening with an inner periphery. The coil is placed inside of the tube so that there is excess circumferential tube material extending from a first end of the coil. The excess circumferential material of the tube is then inserted through the opening at the center of the coil and drawn through the coil to the second end. The edges of the tube which extend from the second end of the coil are then folded back around the outside of the coil and sealed to secure the tube on the roll.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for wrapping a rolled material, particularly a roll or coil of metal, such as steel or aluminum.

2. Description of the Related Art

In steel mills the steel is often made in sheets having a length many times greater than its width. The sheets are wound into coils for compactness during storage. The coils of steel may be stored on pallets for ease in moving and manipulating the coils. It is desirable to wrap the coils of steel in material which is relatively impermeable to water to prevent corrosion of the steel during storage and transport. The process of wrapping coils of metal, and particularly large coils of sheet steel, is labor intensive and costly. There is a need for an efficient method for wrapping coils for transport and storage.

Japanese Patent No. 2-127,271, published May 15, 1990, discloses a strip of packaging material having two edges and a plurality of cuts formed along each edge to form tongues which overlap. The strip further includes an adhesive agent attached to the tongues. The strip is intended to make the process of wrapping steel coils easier.

Neither the Japanese '271 patent nor any other apparatus or method of packaging coils of which the present inventor is aware, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus a method of packaging coils solving the aforementioned problems is desired.

SUMMARY OF THE INVENTION

The method of packaging coils uses a tear-resistant packaging tube having openings at either end. The tear resistant packaging tube is made from at least one layer of material. The coil is generally cylindrical and defines a length, a circumference, an inside diameter, and an opening with an inner periphery. The coil is placed inside of the tube so that there is excess circumferential tube material extending from a first end of the coil. The excess circumferential material of the tube is then inserted through the opening at the center of the coil and drawn through the coil to the second end. The edges of the tube which extend from the second end of the coil are then folded back around the outside of the coil and sealed to secure the tube on the roll.

A packaging tube according to one embodiment of the present invention includes at least one rectangular sheet of a polymeric material, having a first edge, an opposing second edge, a third edge, and an opposing fourth edge. The tube is formed by folding the sheet along a line bisecting the sheet and sealing the first and second edges together. The sheet may be impregnated with a volatile corrosion inhibitor or a multi-purpose inhibitor to prevent deterioration of the coil by corrosion. The sheet may be a multi-layered material semi-laminated around the periphery and/or at continuous or discontinuous intervals across the width or length of the sheet.

These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an environmental, perspective view of a packaging tube about to be placed over a coil according to one embodiment of the method of packaging coils according to the present invention.

FIG. 2 is a perspective view of a sheet of polymeric material used in a method of packaging coils according to the present invention, one end being separated and folded back to illustrate the structure.

FIG. 3 is a perspective view of a packaging tube after the initial step of placing the tube on the coil according to the method of the present invention, showing the excess circumferential material extending from one end.

FIG. 4 is a perspective view showing inner and outer diameter protectors positioned on the coil according to the method of the present invention.

FIG. 5 is a perspective view showing the packaging tube being folded axially to form a snug fit around the steel coil according to the present invention.

FIG. 6 is a perspective view showing the packaging tube being folded and taped down to form a snug fit around the coil according to the method of the present invention.

FIG. 7 is a perspective view showing the excess circumferential material being inserted through the opening at one end of the coil according to the method of the present invention.

FIG. 8 is a perspective view showing the excess circumferential material being drawn through the end of the coil opposite the end shown in FIG. 7 according to the method of the present invention.

FIG. 9 is a perspective view showing the excess circumferential material folded back around the end of the coil shown in FIG. 8 according to the method of the present invention.

FIG. 10 is a perspective view showing a strap disposed around the excess circumferential material and sealing the tube closed according to the method of the present invention.

FIG. 11 is a perspective view of a packaging tube according to another embodiment of the present invention that is separated at opposing edges for receiving steel coil.

FIG. 12 is a perspective view of a steel coil disposed upon the packaging tube of FIG. 11 according to another embodiment of the method of packaging coils of the present invention.

Similar reference characters denote corresponding features consistently throughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to a method for packaging coils for transport or storage. The coils are wrapped in packaging tubes made from flexible material, such as plastic. The coil has a length, a circumference, opposing first and second ends, and an inside diameter defining an opening with an inner periphery. When the coil is a large coil, e.g., a coil of sheet steel, the coil may be lifted, e.g., by a forklift, as shown in FIG. 1, so that the tube 10 may be slipped over the coil S.

The tube 10 may be formed in any suitable manner from one or more layers of a tear resistant, polymeric material. In one embodiment, the tube 10 is made from an appropriately sized rectangular or square sheet of polymeric material. As shown in FIG. 2, the sheet 11 includes a first edge 12, an opposing second edge 14, a third edge 16, and an opposing fourth edge 18. The sheet 11 is folded along a line bisecting the sheet. The first 12 and second edges 14 are sealed by any appropriate means (e.g., adhesive, heat, ultrasonic welding, etc.) and formed into a tube 10 with a single, longitudinally extending seam. At least one layer may be impregnated with a volatile corrosion inhibitor, such as sodium nitrite, or a multi-purpose inhibitor. Examples of a tear resistant polymeric material which may be used include a woven polyethylene or polypropylene material, or a nonwoven material, including both polyethylene and polypropylene. The material can be of any suitable thickness. Preferably, the material ranges in thickness from 0.002 inch to 0.020 inch. The method is illustrated in FIGS. 1-11. Further, the sheet may be a single layer of material, or multiple layers joined together by semi-lamination about the periphery of the two layers. Alternatively, the multiple layers may be joined together by semi-lamination continuously or discontinuously across the width or length of the layers.

As shown in FIG. 3, the coil is placed inside of the tube so such that there is excess circumferential tube material 20 extending from a first end of the coil, while the opposite end of the tube is essentially flush with the second end of the coil. At this stage, an inner diameter protector I may optionally be disposed within the inner diameter of the roll and an outer diameter protector O may optionally be disposed at the outer diameter of the roll, as shown in FIG. 4. The inner and outer diameter protectors, I and O, respectively, can be made from high-density fiberboard, or other suitable material. If the diameter of the tube 10 is too large to provide a snug fit for the roll, it may be necessary to fold the tube axially and tape it down as shown in FIGS. 5-6.

The excess circumferential material 20 of the tube 10 is then inserted through the opening at the first end of the coil, as shown in FIG. 7, and drawn through the hollow core of the coil and out the second end of the coil, as shown in FIG. 8. The excess circumferential material 20 is then folded back over the outside surface of the coil at the second end, as shown in FIG. 9. The free end of the tube 10 is then sealed by any suitable means. FIG. 10 a strap is shown wrapped around the folded ended of the tube 10 so that the tube 10 is firmly secured to the coil, overlapping the opposite end of the coil and effectively hermetically sealing the coil within the tube packaging. The sealing means may be a metal strap, a nylon strap, adhesive tape composite material, vinyl or plastic strapping, or other fastening means.

In some manufacturing facilities, it may be impractical to lift the coil with a forklift in order to pull the tube 10 over the coil S. In these situations, it may be necessary to temporarily separate edges, 12 and 14, in order to place the coil on top of the sheet 11, as shown in FIGS. 11-12, and then wrap the edges 12 and 14 around the coil and reseal the edges 12 and 14. The excess circumferential material 20 is then inserted through the coil and folded over the outside of the coil as described above.

The method of the present invention is capable of being carried out using tubing constructed of various materials, formed into tubing by various methods, and packed or sold in different forms. Although the tubing has been described as being made from rectangular sheets of plastic material subsequently formed into tubes, nevertheless, the method includes tubing made from plastic, textiles, wovens, nonwovens, films, mixtures of poly-materials with cellulose (also known as Kraft, natural Kraft, or Kraft paper), poly base extrusion, composites, or other suitable material.

Further, the tubing may be made from a single layer of material, or from multiple layers of material either fully laminated together or partially laminated together, as described above. When formed from multiple layers, the material comprising the layers may be the same material or different materials, e.g., a layer of Kraft paper bonded or laminated to a layer of plastic by extrusion, adhesive, chemical bonding, etc.

The packaging tube may be formed from rectangular sheets having opposing sides bonded together axially as described above, or may be formed as a seamless tube by extrusion through an appropriate die, or in any other manner known in the art for forming a tube of material. The tubing may also be sealed across one end to form a bag in some embodiments. The tubing may be supplied as individually sized tubes or bags for coils of specific sizes, in rolls perforated at selected intervals for easily detaching a length of tubing for coils of specific sizes, or in continuous rolls that the customer can cut to any desired length.

It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. 

1. A method of packaging a coil, the coil having a hollow core defining an axis and opposing first and second axial ends, the method comprising the steps of: (a) placing the coil into a tube of flexible packaging material, the tube having a greater length than a distance defined between the first and second axial ends of the coil, so that a first end of the tube is substantially flush with the second end of the coil and a second end of the tube includes excess tube extending from the first end of the coil; (b) inserting the excess tube into the first end of the coil; (c) drawing the excess tube through the hollow core of the coil and out the second end of the coil; (d) folding the excess tube over the second end of the coil so that the second end of the tube overlaps the first end; and (e) sealing the second end of the tube over the first end of the tube.
 2. The method of packaging a coil according to claim 1, further including the step of placing an inner diameter protector over at least one of the axial ends of the coil.
 3. The method of packaging a coil according to claim 1, further including the step of placing an outer diameter protector over at least one of the axial ends of the coil.
 4. The method of packaging a coil according to claim 1, further comprising the step of forming the tube from a rectangular sheet of flexible plastic material.
 5. The method of packaging a coil according to claim 4, wherein said forming step further comprises the steps of: folding the rectangular sheet in half to approximate opposing sides of the sheet; and sealing the opposing sides together to form the tube.
 6. The method of packaging a coil according to claim 1, wherein said flexible packaging material comprises a tear resistant plastic material impregnated with a volatile corrosion inhibitor.
 7. The method of packaging a coil according to claim 1, wherein said flexible packaging material comprises a tear resistant plastic material impregnated with a multi-purpose inhibitor.
 8. The method for packaging a coil according to claim 1, wherein step (e) further comprises fastening a strap around the second end of the tube adjacent the second end of the coil.
 9. The method for packaging a coil according to claim 1, wherein the strap is made from a material selected from the group consisting of metal, nylon, vinyl, plastic, and a composite.
 10. The method for packaging a coil according to claim 1, wherein step (e) further comprises fastening the second end of the tube around the first end of the tube by adhesive tape.
 11. The method for packaging a coil according to claim 1, wherein step (a) further comprises the steps of: splitting the first end of the tube; laying the tube upon a support surface with the split first end folded open; placing the coil on the first end of the tube; folding the split end around the coil axially; and re-sealing the split first end of the tube.
 12. A packaging tube, comprising at least one rectangular sheet of a plastic material, the sheet being impregnated with an inhibitor and having a first edge, an opposing second edge, a third edge, and an opposing fourth edge. the sheet being folded along a line bisecting the sheet, the first and second edges being sealed together axially to form the tube.
 13. The packaging tube according to claim 12, wherein said inhibitor comprises a volatile corrosion inhibitor.
 14. The packaging tube according to claim 12, wherein said inhibitor comprises a multi-purpose inhibitor.
 15. The packaging tube according to claim 12, wherein said sheet is made from polyethylene.
 16. The packaging tube according to claim 12, wherein said sheet is made from polypropylene.
 17. The packaging tube according to claim 12, wherein said sheet is made from a plurality of layers semi-laminated together about their periphery.
 18. The packaging tube according to claim 12, wherein said sheet is made from a plurality of layers semi-laminated together continuously or discontinuously across the width of the sheet.
 19. The packaging tube according to claim 12, wherein said sheet is made from a plurality of layers semi-laminated together discontinuously across the length of the sheet.
 20. The packaging tube according to claim 12, wherein said sheet is made from a plurality of layers semi-laminated together continuously across the length of the sheet.
 21. A packaging tube, comprising at least one sheet of a material impregnated with an inhibitor and formed into a cylinder.
 22. The packaging tube according to claim 21, wherein said inhibitor comprises a volatile corrosion inhibitor.
 23. The packaging tube according to claim 21, wherein said inhibitor comprises a multi-purpose inhibitor.
 24. The packaging tube according to claim 21, wherein said sheet is made from at least one material selected from the group consisting of plastic, textiles, wovens, nonwovens, films, mixtures of poly-materials with cellulose, Kraft, a poly base extrusion, and composites.
 25. The packaging tube according to claim 21, wherein said sheet is made from a plurality of layers.
 26. The packaging tube according to claim 25, wherein said layers are fully laminated together.
 27. The packaging tube according to claim 25, wherein said layers are semi-laminated together.
 28. The packaging tube according to claim 25, wherein said layers are made from materials of identical composition.
 29. The packaging tube according to claim 25, wherein said layers are made from materials of different composition.
 30. The packaging tube according to claim 21, wherein said cylinder is formed with an axial seam.
 31. The packaging tube according to claim 21, wherein said cylinder is seamless.
 32. The packaging tube according to claim 21, wherein said cylinder is formed by extrusion.
 33. The packaging tube according to claim 21, wherein said cylinder is formed by extrusion of a plurality of layers of material.
 34. The packaging tube according to claim 21, wherein said sheet is made from a plurality of layers semi-laminated together about their periphery.
 35. The packaging tube according to claim 21, wherein said sheet is made from a plurality of layers semi-laminated together continuously or discontinuously across the width of the sheet.
 36. The packaging tube according to claim 21, wherein said sheet is made from a plurality of layers semi-laminated together discontinuously across the length of the sheet.
 37. The packaging tube according to claim 21, wherein said sheet is made from a plurality of layers semi-laminated together continuously across the length of the sheet.
 38. The packaging tube according to claim 21, wherein said cylinder is sealed across one end, thereby forming a bag.
 39. The packaging tube according to claim 21, wherein said cylinder is formed into a roll for storage.
 40. The packaging tube according to claim 39, wherein said roll is continuous, whereby the cylinder is custom-cut to length.
 41. The packaging tube according to claim 39, wherein said roll is perforated at uniform intervals, whereby cylinders of uniform length are detachable from said roll at the perforations.
 42. The packaging tube according to claim 21, wherein the sheet is made from a tear-resistant material. 